


Ag and Au

by LollyHolly99



Category: Undertale (Video Game)
Genre: Alternate Universe - Underfell, Gen, Other Additional Tags to Be Added
Language: English
Status: In-Progress
Published: 2017-12-19
Updated: 2017-12-19
Packaged: 2019-02-16 20:46:56
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 2,517
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13061844
Author URL: https://archiveofourown.org/users/LollyHolly99/pseuds/LollyHolly99
Summary: Sans stumbles into Underfell and meets a new friend. Not so great times ensue.Based on an idea from tumblr user withtheworms in which UT!Sans and UF!Sans meet up and Red brings out the worst in Sans.(On indefinite hiatus)





	Ag and Au

**Summary for the Chapter:**

> Sans lands in an unfamiliar place and meets... himself?

**Notes for the Chapter:**

> asdsf so like?? i just fell in love w/ this idea sooo here's a few thousand words (and more planned!) that i barfed out in appreciation of Silver Fang Snas  
> ty Wormy I only hope this and future chapters live up to what I want them to be  
> and @ all y'all hope you enjoy my dumb writings. complain to me abt em or the fact that i'm starting smth new without finishing smth else first Yet Again @ lollyholly99.tumblr.com B)  
> <3  
> (also it may end up getting a little/a lot kustardy later. depends on how i feel. just warning folks now)  
> (also I'm wAY TOO PROUD OF THIS TITLE IT'S LIKE 5 DIFFERENT USES OF WORDPLAY IN 1 ASSDFDFD)

Sans didn't know what the hell happened.

Bright white.

Then an empty black.

Then white again, blinding, that faded, further, further, until he could see properly again at last.

_Sans didn't know what the hell happened._

His surroundings came into view. A familiar tiled room - of course it was familiar, he'd just been there. And it was, of course, _his_ workshop. He saw the ceiling, mostly. He was flat on his bony ass on the floor. And also a little dizzy.

Man, that'll teach him not to screw with mysterious machines in his workshop that he barely knows the function of. Well, It was something to do with spacetime, he knew that at least. Which only made his decision to mess around with it all the wiser, of course.

Sans sat up, rubbing his skull in the wake of his disorientation. Well, he wasn't dead, or injured, from what he could tell, so it hadn't been a complete catastrophe.  
"just leaves something worse to have happened." he muttered to himself, chuckling a little, unsurely.

He debated with himself whether getting up and trying to revert whatever he might have done to the machine or leaving it as is was the better idea in his situation. Who knew what that thing would do in either case?

Sans decided to leave it for now, opting to reverse any alterations if things got too weird. Or bad. At the moment, the plan was just to collect up his tools and put them away, starting with the wrench that... he'd dropped... right in front of the machine...

...

...Where the heck did it go?

His eye lights moved around the room confusedly. It had been right there, just a few moments ago, he was certain of that.

Getting up finally, he searched about the workshop, but couldn't even find the toolbox he'd brought down with him.

What the hell? Did the machine have something to do with this? Did it, perhaps, like himself, have a penchant for pranks and jokes, and moved the tools for a laugh? Heh. What an outcome that'd be. Mysterious spacetime machine turns out to be sentient, and all it does is move things to screw with people. Hilarious.

 _that probably ain't gonna be the case, though,_ he thought. _with my luck, it's gonna end up being a lot worse, ain't it?_

Maybe Papyrus just found out about the workshop and wandered in and Sans had been unconscious for longer than he thought and Pap thought he was sleeping and cleaned up his tools and took them to the shed? Hmm... No, too many holes in that theory. He counted that one out immediately, coming to the conclusion that the machine definitely did something.

He noticed for a second that something felt particularly odd about his workshop now, but he couldn't quite put his finger on it...

Sans' train of thought was interrupted by a noise, a thumping from the direction of the stairs and the door. Stomping, for sure. And then the sound of the lock on the door being fiddled with. But who would...

The door was flung open, Sans could tell. He'd heard it slam against the wall a few times when he'd frustratedly swung it open - enough times to know. But then there was a sound he didn't know. A voice. Or _did_ he know it? It wasn't dissimilar to his own, almost exactly the same, but gruffer. There was more of a growl to it, a grit he didn't recognise.

"alright ya fuckin' hunk of junk, what're ya makin' noise for now?" the voice spoke, presumably with its owner believing no-one to actually be there to listen.

"stupid goddamn dumbass machine," they grumbled, getting louder as they approached. "middle of the night, soundin' like a bomb went off in the basement. better not be completely trashed, ya little shit..."

Sans felt his soul pound in his ribcage, equal parts fearful and intrigued by the intruder. Machine? They knew about it? They'd heard whatever just happened? They had a key to the workshop? What the hell??

The person Sans had been hearing finally came into view. It was... himself?

Or, rather, some kind of distorted mirror image of him. He was a skeleton monster, yes, and looked almost the same - in build, height, face and all - but his stained blue hoodie was replaced with a black one with a fur-lined hood. The... impostor(?)... had a bright red collar around his neck, the same hue as the glowing lights in the monster's eyesockets. And to top it all off, he had one large golden tooth that glinted under the humming artificial lights above.

Sans would've laughed at how much this guy looked akin to himself during some edgy phase in his teenage years, were it not for the confusion enveloping him.

The other Sans, if that was indeed what he was, turned the corner, yawning.

"alright, let's see what's wrong with y-"

He stopped in his tracks, eyesockets widening for a second when he saw Sans. Then, his surprise turned to confusion.

"huh?"

"what in the hell...?" Sans whispered, the only thing he could do, as frozen as he was.

"the fuck?" 'Sans' said, cocking a brow bone. "is this some kinda joke?" He looked annoyed, angry, even, that Sans was there. Most of all, he looked dangerous.

"wh-" Sans began, but he was interrupted by the other Sans rushing foward and pushing him back by his neck, pinning him to the wall behind him.

"who are ya?" the red Sans growled, glowering at him. "and what're ya doin' here?"

"i could ask you the same thing." Sans managed to say, chuckling despite, or perhaps because of, his nerves. "i'm, uh, sans. this is my basement. now, you mind letting me go so we can tal-"

He was cut off again, this time by the other Sans delivering a swift, hard punch to his jaw.

"yeah? well guess what, ya knock-off fuck, _i'm_ sans. and you, ya fucked up tryin' to be some impostor of me, idea _and_ execution, and ya better tell me who ya really are before i dust ya."

So... he was Sans? But not...?

...Oh.

It suddenly dawned on Sans what the situation must be.

"oh shit, the timelines..." Sans uttered under his breath.

The other Sans hit him again. "speak up, asshole, who are ya?!"

"i'm sans. you're sans too." Sans explained, hurriedly, but as calmly as he could while being threatened like he was. "we both are, we're from-"

The other Sans punched him one more time, even harder, making a terrible cracking sound as his fist connected with his jaw. Then he heard something clatter to the floor, making him look down. A tooth. Another second later and he tasted the thick red liquid slowly seeping from where the tooth had been.

"c'mon, quit fuckin' around, i-"

"what do you know about timelines?" Sans questioned, instantly taking the other him aback. He felt his grip weaken around his vertebrae.

"...you... huh? how'd ya know about tha-"

While the other Sans was disoriented, Sans took the opportunity to escape from his hold. His eye flared blue, and the other's soul went blue similarly. A second later, and he'd been flung backwards, landing on the floor with a grunt. He looked up at Sans, rubbing his skull.

"gah, you fucker... how do you know about the timelines?!"

"chilled out yet?" Sans asked confidently before summoning his tongue to poke and prod and the newly made gap in his jaw a little.

The Sans on the floor stood again. "i'll be 'chill' when i find out what the hell's goin' on!"

"well," Sans began. "my theory right now's that we're eachother. from different timelines."

Red Sans' eyesockets widened. "shit, that's why ya look like me, but all weird, ain't it?"

"weird? heh, might wanna look at yourself there, bud."

Sans smirked, and the other Sans smirked back.

"actually, _bud_ , i am."

"heh."

"heh."

There was a beat, they calmed down, and then the red Sans spoke again.

"so, how'd ya get here?" he asked.

"uh, i could ask the same thing? how do you know this ain't _my_ timeline that _you_ came to?"

"i was literally just outside, pal, i think i know what my own universe looks like."

Sans nodded in agreement. "true. and that does explain my toolbox... anyway, i can only assume that machine did it. or, my one, i guess. i was tinkering with it and suddenly... i dunno, man, i think i got knocked out somehow, then i woke up in here."

"what, so you got the same shitty pile of scrap metal in your basement? huh. i thought it had somethin' to do with timelines. nice to have that confirmed."  
Red Sans sauntered past Sans, to the machine, and crouched by it, inspecting it closely. "now the question is... what the fuck did ya do to get here, and how do we get ya back to your own timeline?"

"beats me. heh, that'll learn me a lesson, huh?"

Other Sans didn't respond, only opening up part of the machine and fiddling with parts inside. "man, i don't even fuckin' know how i'm gonna get this thing to get ya back home."

Sans' grin fell a little at the lack of response. "you're, uh, real eager to get me back there, aren't you?"

"well, yeah," the other Sans said, still looking inside the machine. "'s not like i wanna keep ya around takin' up space in my home and everythin' any longer than i need."

Sans shrugged. "fair enough."

"and, y'know..." red Sans continued, looking up at him. "you've got a papyrus back home, don'tcha?"

"oh... yeah." Sans realised in that moment that Papyrus was still back home, all alone. Probably going to look for him soon. Probably going to be worried sick about his big brother when he eventually can't find him anywhere.

Sans shook his head. "nah, he'll be fine. wouldn't be the first time i disappeared for a while."

"ya ever disappear for a couple days?"

"damn, you think this'll take that long?"

"just estimatin'. anyways, i didn't mean paps ain't gonna be okay," He turned to face Sans. "i meant you might not be okay."

Sans looked back at him, perplexed. "huh? i mean, yeah, shit, pap's half the reason i get up in the morning, but it's not like i'm gonna die without him."

"no, dumbass, i mean when ya get back. if your papyrus is anythin' like mine, and you're as weak as ya look, you're gonna get your ass kicked for bein' away like that, and it's gonna be a bad time."

"dude, papyrus would never. he's cool. the coolest."

"well, yeah, that last bit's true, but-"

"nice to know you care about me though, heh."

The other Sans scowled at him. "ya must be delusional, buddy. i don't 'care', i just want ya outta here. this universe ain't big enough for two different sanses, and i don't wanna deal with the shit fate's gonna give us from you bein' here."

"then why'd you warn me about paps kicking my ass?" Sans retorted immediately, smirking. "i'm thinking this is some situation like... what's that thing alphys mentions from time to time in her animes... tsundere?"

"fuck off."

"c'mon, man, i thought you'd like a little joking around at a time like this."

"go fuck yourself."

"well, we're pretty handsome guys... a pretty handsome guy? but i wouldnt've thought you were in the mood right n-"

The red Sans stomped up to him and grabbed him by the collar of his shirt. Sans' smile fell.

"are ya gonna help me getcha the fuck outta here, or are ya gonna keep screwin' around and makin' shittier jokes than mine?"

Sans wondered whether he should prod him further.

Yes.

"wow, mood swings, much?"

The other Sans growled at him again, and summoned his Gaster blasters, pointing them at Sans as a threat.

Without saying a word, Sans summoned his own, pointed at his double similarly in response. At that, the other Sans dissipated his blasters, standing down and letting go of Sans' t-shirt. Sans dismissed his in turn a second later.

"y'know," Sans piped up. "i think we got off on the wrong foot. how about we try this again? hey, me, i'm you." He held out his hand for the other to shake as a sign of peace.

The red Sans did so, somewhat reluctantly, still slightly pissed off, and suddenly, the sound of a fabricated fart and a buzzing sounded simultaneously.

The two couldn't hold in their laughter. Whoopie cushion and a joy buzzer in the handshakes? Yup, they really were both Sanses.

"alright, alright, fine." red Sans said once they'd calmed down again. "we'll be 'pals' now, or what-the-fuck-ever."

"yeah. nice."

Other Sans began to walk out, and motioned for Sans to follow him. "well, c'mon. may as well get some sleep so we can get started on this shit tomorrow."

"alrighty."

Sans followed him out of the workshop (which they'd made sure to lock up) and round to the front of the house. He looked around curiously at his surroundings in this unfamiliar timeline.

Snowdin looked enough the same to feel like home, but at the same time, vastly different. The houses looked dilapidated and uncared for, and the atmosphere of the whole town felt as cold as the snow beneath his feet. In his Snowdin, people could be found in the street, enjoying eachother's company and smiling and having fun, even late at night, like this, whereas in this strange Snowdin, the only other traces of life he could find right now were scurrying shadows off in the distance, beyond the trees. It was unsettling, to say the least.

He was snapped out of his disturbed trance when they reached the front door, and almost bumped into the other him, who had stopped walking.

"you can bunk on the couch. i don't think i gotta tell ya where anythin' is, it's gonna be the same in your timeline, right?" he said, opening up the door and leading Sans to the living room.

Sans shrugged. "i mean, i'd assume so."

"alright. see ya tomorrow." other Sans responded, heading upstairs.

"hey, hold up,"

"huh?"

"i was wondering, mind if i call you red?"

"'red'?" The other Sans looked at him quizzically.

"yeah. i've been calling you 'red me' and 'other me' and stuff in my head, may as well shorten it to something easier. and something less confusing than just 'sans'."

He deliberated on it for a moment before nodding. "yeah, fine. red it is."

"nice. you wanna pick a name for me?"

"hmm... how's about 'asshat'?"

Sans winked. "how about cl- _ass_ -ic? 'cause i know all the best jokes."

" _how's about_ comic, since ya seem to be strugglin' worse than me to go five minutes without tellin' a fuckin' joke?"

"i'm good with that."

Red sighed. "i didn't mean it, but... fuck it, whatever floats your boat, i guess."

"awesome. night, red."

"yeah, yeah, see ya tomorrow."


End file.
